Thermal stress is an important factor influencing the strength of a heat exchanger tubesheet. Some studies have indicated that, even in floating-head or U-tube heat exchangers, the thermal stress at the tubesheet is significant in magnitude. For exploring the value, distribution, and the influence factors of the thermal stress at the tubesheet of these kind heat exchangers, a tubesheet and triangle arranged tubes with the tube diameter of 25 mm were numerically analyzed. Specifically, the thermal stress at the tubesheet center is concentrated and analyzed with changing different parameters of the tubesheet, such as the temperature difference between tube-side and shell-side fluids, tubesheet diameter, thickness, and the tube-hole area ratio. It is found that the thermal stress of the tubesheet of floating-head or U-tube heat exchanger was comparable in magnitude with that produced by pressures, and the distribution of the thermal stress depends on the tube-hole area and the temperature inside the tubes. The thermal stress at the center of the tubesheet surface is high when tube-hole area ratio is very low. And with increasing the tube-hole area ratio, the stress first decreases rapidly and then increases linearly. A formula was numerically fitted for calculating the thermal stress at the tubesheet surface center which may be useful for the strength design of the tubesheet of floating-head or U-tube heat exchangers when considering the thermal stress. Numerical tests show that the fitted formula can meet the accuracy requirements for engineering applications.

References

References
1.
Gardner
,
K. A.
,
1948
, “
Heat Exchanger Tube Sheet Design
,”
ASME J. Appl. Mech.
,
15
(
4
), pp.
377
385
.
2.
Gardner
,
K. A.
,
1969
, “
Tube Sheet Design: A Basis for Standardization
,”
First International Conference on Pressure Vessel Technology
, Delft, The Netherlands, Sept. 29–Oct. 2, pp.
621
648
.
3.
China standards
,
2014
, “
Heat Exchanger
,” Standards Press of China, Standard No. GB/T 151-2014.
4.
French standards
,
2005
, “
Code for Construction of Unfired Pressure Vessels
,” SNCT publications, Standard No. CODAP-2005.
5.
American Standards
,
2007
, “
Standards of the Tubular Exchanger Manufacturers association
,” TEMA,
Standard No. TEMA-2007
.
6.
Gardner
,
K. A.
,
1942
, “
Heat Exchanger Tube Sheet Temperatures
,”
Refin. Nat. Gasoline Manuf.
,
21
, pp.
71
77
.
7.
Wu
,
Q. S.
, and
Xue
,
M. D.
,
1998
, “
Analysis Method of Temperature Fields in Tubesheets of Tubular Heat Exchangers
,”
Nucl. Power Eng.
,
19
(
5
), pp.
401
407
.
8.
Liu
,
M. S.
,
Dong
,
Q. W.
,
Wang
,
D. B.
, and
Ling
,
X.
,
1999
, “
Numerical Simulation of Thermal Stress in Tube-Sheet of Heat Transfer Equipment
,”
Int. J. Pressure Vessels Piping
,
76
(
10
), pp.
671
675
.
9.
Hu
,
X. W.
, and
Lin
,
X. H.
,
2004
, “
Heat Exchanger Tubesheets Stress Research by Finite Element Analysis
,”
Pressure Vessel Technol.
,
121
(
10
), pp.
26
28
.
10.
Xu
,
L.
,
Qian
,
C. F.
,
Liu
,
J. Y.
, and
Liu
,
Z. S.
,
2015
, “
Thermal Stress Analysis at the Tubesheet of Floating-Head Heat Exchangers
,”
Pressure Vessel Technol.
,
32
(
6
), pp.
50
55
.
11.
Ando
,
M.
,
Takasho
,
H.
,
Kawasaki
,
N.
, and
Kasahara
,
N.
,
2013
, “
Stress Mitigation Design of a Tubesheet by Considering the Thermal Stress Inducement Mechanism
,”
ASME J. Pressure Vessel Technol.
,
135
(
6
), p.
061207
.
12.
Ando
,
M.
,
Hasebe
,
S.
,
Kobayashi
,
S.
,
Kasahara
,
N.
,
Toyoshi
,
A.
,
Ohmae
,
T.
, and
Enuma
,
Y.
,
2014
, “
Thermal Transient Test and Strength Evaluation of a Tubesheet Structure Made of Mod.9Cr–1Mo Steel. Part II: Creep-Fatigue Strength Evaluation
,”
Nucl. Eng. Des.
,
275
, pp.
422
432
.
You do not currently have access to this content.